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  • 1
    Electronic Resource
    Electronic Resource
    N-Fluoro-2,6-dimethylpiperidines. Conformational behavior as observed by fluorine-19 nuclear magnetic resonance (1971)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 93 (1971), S. 5263-5265 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00749a054
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  • 2
    Electronic Resource
    Electronic Resource
    Episyénitisation dans le Gisement d'Uranium du Bernardan (Marche): Comparaison avec des Gisements Similaires du Nord-Ouest du Massif Central Français (1984)
    Springer
    Mineralium deposita 19 (1984), S. 26-35 
    Details
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Abstract The Bernardan uranium deposit, mined in the Marche Occidentale two-mica granite, is a disseminated type deposit. Similar deposits are known in hercynian belt. Uraniferous mineralizations (pitchblende, coffinite, black minerals, autunite, ...) are disseminated in a vuggy rock called “episyenite”. It results from an hydrothermal alteration of the granite by hot aqueous solutions (370 to 260°C, 2–5.7 wt% equiv. NaCl). Quartz is dissolved; feldspars (mainly plagioclases) and biotites are partially transformed into phengites. Granitic muscovites and orthoclases are reequilibrated with loss of sodium. This alteration is controlled by fractures at several scales. Such an alteration can be observed in other deposits of the North West part of the French Massif Central, as Margnac and Fanay in the St Sylvestre massif and Hyverneresse in the Millevaches massif. Mineralogical transformations except the content in secondary phengites, chemical changes (SiO2 decrease and potassic metasomatism), P-T conditions and tectonic control are the same in all these deposits.
    Notes: Résumé Le gisement d'uranium du Bernardan exploité dans le granite à deux micas de la Marche Occidentale appartient au groupe des gisements «d'imprégnation». La minéralisation uranifère (pechblende, coffinite, «produits noirs», autunite, ...) est disseminée dans une roche vacuolaire appelée «épisyénite». Cette dernière résulte d'une altération hydrothermale du granite par des solutions chaudes (370–260°C; 2–5,7% poids équiv. NaCl). Le quartz est dissout; les feldspaths (principalement les plagioclases) et les biotites sont partiellement transformés en phengites. Les muscovites et orthoses granitiques se réequilibrent avec perte de sodium. Cette altération est guidée par un réseau de fractures à différentes échelles. Une altération comparable a été observée dans d'autres gisements du Nord Ouest du Massif Central français, comme Margnac et Fanay dans le massif de St Sylvestre et Hyverneresse dans celui du Millevaches. Les transformations minéralogiques, à l'exception de la quantité de phengites secondaires, les changements chimiques (lessivage de silice et métasomatisme potassique), les conditions P-T et le contrôle tectonique sont les mêmes dans tous ces gisements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206594
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  • 3
    Electronic Resource
    Electronic Resource
    An expeditious synthesis of 3-fluoroacrylic acid (1993)
    s.l. : American Chemical Society
    The @journal of organic chemistry 58 (1993), S. 3772-3774 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo00066a035
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  • 4
    Electronic Resource
    Electronic Resource
    Facile synthesis of ethyl 3,3-difluoroacrylate from dibromodifluoromethane and Diels-Alder cycloaddition with furan (1987)
    s.l. : American Chemical Society
    The @journal of organic chemistry 52 (1987), S. 290-292 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo00378a028
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  • 5
    Electronic Resource
    Electronic Resource
    Maximum optical rotation of 2-fluorooctane? A survey of fluorinating reagents (1979)
    s.l. : American Chemical Society
    The @journal of organic chemistry 44 (1979), S. 3406-3408 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo01333a030
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  • 6
    Electronic Resource
    Electronic Resource
    1,2-Difluoroethylenes: synthesis via fluoro ketones (1981)
    s.l. : American Chemical Society
    The @journal of organic chemistry 46 (1981), S. 206-209 
    Details
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jo00314a055
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  • 7
    Electronic Resource
    Electronic Resource
    Melt and fluid inclusions from volcanic quartz phenocrysts in the Shila gold / base metal ore district, Peru: precursors to ore-forming epithermal solutions? (2002)
    Oxford, UK : Blackwell Science Ltd
    Terra nova 14 (2002), S. 0 
    Details
    ISSN: 1365-3121
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: Despite the close association with volcanic activity, the source of metals and ligands in the epithermal ore deposits is still controversial. In order to explore the magmatic–hydrothermal connection further, silicate melt, saline- and water-rich fluids, and CO2 vapours are documented that are trapped as inclusions in quartz phenocrysts from dacitic dykes associated with epithermal gold/base metal mineralization in the Shila district (Peru). Melt inclusion characteristics, and microthermometric and laser Raman fluid inclusion data are presented. The investigation of melt and fluid inclusions reveals that the volatile phase of magmas might represent the precursors to the early chlorine-rich ore-forming epithermal solutions. Microthermometric investigations in magmatic quartz crystals and data on quartz mineralized veins suggest that the fluid evolution and ore deposition may be the result of several processes including: release of an evolving magmatic fluid, and/or boiling, and/or mixing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3121.2002.00435.x
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  • 8
    Electronic Resource
    Electronic Resource
    Motor abnormalities of digestive and urinary tracts in patients on ventilator for acute exacerbation of chronic obstructive pulmonary disease (1989)
    Springer
    Digestive diseases and sciences 34 (1989), S. 1231-1237 
    Details
    ISSN: 1573-2568
    Keywords: colonic transit time ; pseudoobstruction ; respiratory insufficiency ; mechanical ventilation ; chronic obstructive pulmonary disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The frequency of digestive motor abnormalities was evaluated in 30 consecutive patients ventilated for acute exacerbation of chronic obstructive pulmonary disease. Total and segmental colonic transit times were investigated by radiopaque marker transit time in all patients. Eleven patients also had rectoanal and esophageal manometries, combined with urodynamic study in eight cases. The results show that total radiopaque marker transit time was increased, 201±14 hr (mean±se), with two main regions of decreased transit rates: the right colon (42% of global transit time) and the rectosigmoid (36%). Delayed transit of radiopaque markers in nine of 11 cases was combined with esophageal motor dysfunction and absence of rectoanal inhibitory reflex. In three of eight cases there was disinhibition of urinary bladder contraction, and micturition was impossible in two of eight cases. We conclude that patients on ventilator for exacerbation of chronic obstructive pulmonary disease always have a delayed colonic transit time with diffuse digestive and bladder motor dysfunction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01537271
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  • 9
    Electronic Resource
    Electronic Resource
    (β-Octafluoro-meso-tetraarylporphyrin)manganese Complexes: Synthesis, Characterization and Catalytic Behaviour in Monooxygenation Reactions (2000)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 2000 (2000), S. 1097-1105 
    Details
    ISSN: 1434-1948
    Keywords: Fluorinated porphyrins ; Electrochemistry ; Manganese ; Oxidation catalysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and characterization of manganese complexes of β-octafluoro-meso-tetraarylporphyrins are reported. The presence of the electron-withdrawing β-fluorine atoms induces a very large shift of the redox potential for the oxidation of the manganese(II) derivatives. With the meso-aryl group bearing two ortho-chlorine atoms (2,6-dichlorophenyl) or five fluorine atoms (pentafluorophenyl), metal complexation leads to the isolation of pure manganese(II) compounds. The stability and catalytic activity of these new derivatives have been studied using hydrogen peroxide and iodosylbenzene as oxidants, and standard substrates for epoxidation and hydroxylation reactions. The results are compared to those obtained with the β-hydrogenated analogs under the same conditions. In the case of hydrogen peroxide, the high level of porphyrin degradation prevents efficient catalytic activity. With iodosylbenzene as oxidant, both stability and epoxidation are similar to those of the β-hydrogenated porphyrins, however, a substantial improvement in the efficiency of the hydroxylation of cyclohexane is observed with up to 33 turnovers with (perfluorotetraphenylporphyrin)manganese(II).
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    2,3,7,8,12,13,17,18-Octafluoro-5,10,15,20-Tetraphenylporphyrin: First Synthesis and X-Ray Crystal Structure of the ZnII Complex (1997)
    Weinheim : Wiley-Blackwell
    Chemistry - A European Journal 3 (1997), S. 1890-1893 
    Details
    ISSN: 0947-6539
    Keywords: heterocycles ; fluorine ; porphyrinoids ; zinc ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,3,7,8,12,13,17,18-Octafluoro-5,10,15,20-tetraphenylporphyrin has been prepared from 3,4-difluoropyrrole and benzaldehyde under Lindsey conditions. An X-ray crystal structure study of its ZnII complex has shown that the macrocycle core is nonplanar, a result in apparent contradiction with a blue-shifted UV/Vis spectrum. The results reported here demonstrate that a wide range of β-octafluoro-meso-arylated porphyrins, a new class of highly electron-deficient ligands, are potentially accessible from 3,4-difluoropyrrole, thus opening the door to, inter alia, efficient and robust oxidation catalysts.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chem.19970031122
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